Crash on infinity distance

It's hard to reproduce, but sometimes the program will crash at:

dists[i] = sqrt(dists[i]);

inside Classify().

Looks like the dist[0] after the call to the ANN library search function returns infinity for a distance. That or the distance turns to infinity after doing the square root, not sure. Have to look into how this is happening.

I've found that you can reproduce this somewhat regularly by starting a video feed (youtube) and then firing up ProtoType. It ought to crash pretty much right away.